The article addresses the environmental characteristics and factors of motor transport effects on the environment. The amount of harmful substances emitted by a vehicle into the atmosphere is affected by: speed and number of decelerations and accelerations; vehicle condition, quality of repair and maintenance; traffic intensity; climatic conditions in a specific area; and urban development rate. It is shown that the areas of focus in ensuring the environmental safety of motor transport are: limitation of fleet growth; intensive development of transport infrastructure; scientific traffic management; improvement of the environmental characteristics of vehicles; improvement of vehicle maintenance and repair quality; assurance of quality and improvement of automobile operating materials. The article also presents information on environmental exposure to operating materials of vehicles. © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the XIV International Conference 2020 SPbGASU “Organization and safety of traffic in large cities”